Device for removing and replacing the cover of a furnace or the like



Dec. 3, 1957 G. cOORS 2,815,203

DEVICE FOR OVING AND E LACING THE COVER A FURNA THE LIKE Filed June 18, 1954 2 Sheets-Sheet 1 INVENTOR seone cooRs ATTORNEYS Dec. 3, 1957 G. COORS 2,815,203

DEVICE FOR REMOVING AND REPLACING THE COVER OF A FURNACE OR THE LIKE Filed June 18. 1954 2 Sheets-Sheet 2 INVENTOR GEORG COORS WMzM ATTORNEYS 2,815,203 Patented Dec. 3, 1957 DEVICE FOR REMOVING AND REPLACING THE CUVER F 'AFURNACE ORTHE LIKE Georg ,Coors, Wiesbaden, Germany, =assignor to Westofen G. m..'b.zH., Wiesbaden, -Germany,a Germanfirm Application June 18, 1954, Serial No. 437,801

Claims priority,- application Germany Juner20,='1953- 8 Claims. (Cl. 268-10) The present invention relates to apparatus for removing and replacing-the cover of a furnace, soakingpit or.

the like.

In many furnaces, soaking pits and the like, the material to be treated-is charged or introduced into the pit or furnace, and is discharged or withdrawn therefrom, through the top. For this purpose, the flat or arched cover of the pit obfurnace, which tightly closes thepit or furnace chamber or interior at the top thereof, is raised from its closing position and moved'awayfrom the pit or furnace opening and, after rechargingof the pit or furnace, is replaced in su-ch closing position. The usual-size-of such a cover and the temperature at which it is generally found, necessitate the employment of special apparatus forthese removing and replacing operations.

Lifting and transporting-devices for such covers are known- Conventionally, the-said devices ride on rails provided at one side near the pit or furnace opening. However, in such devices, the assemblieswhich raise and lower the cover and which operate the device, especially the motors and gear drives, are positioned on the cover; i. e. above the pit orfurnace opening- Consequently, the-driving assemblies, which comprise heatsensitive material-for example, motors and the insulation thereon-are prejudicially exposed,whenthe cover is inclosed position, to appreciable indirect heat radiation'from thencover and, when the -cover is in removed position,-.to intensive direct heat radiation. In addition, the devices provide a direct :liftfor-the cover and 'also hold the entire weight of the coveras a suspended load,

so that very large driving :or operating units are required.

It is an object of the present invention to embod-ya relationship .of parts for-effecting the aforesaid functions, i. e..:removing and-replacing the cover of the pit or furnace, while being free of therprior art deficiencies and defects.

In copending. application,' .-Ser..No. 424,481,;apparatusis disclosedand claimed for obviatingtthev afore-outlined defects. of the prior art.

well as for supporting the cover are. disposed on a movable; carriage exteriorly of the extent of the cover, i. e. beyond .thesurface of the latter.

The presentinvention solves the .problemin a somewhat different way, whereby a special and separate cover carrying carriageis dispensed with; Briefly stated, the relationship of parts according to the present inventionis characterized .by the fact that. cover is directly movably mounted on. a runway, or tracks positioned near theufurnace chamber, and by the fact that the section of the runway or tracks which supports the cover in its position above the furnace chamber is constructed so that such sectioncan be raised and lowered. In the closing position of the cover, the track section is depressed (lowered) relative to the plane of the trackway. By lifting the said section, the cover is lifted from its closing position and the section is brought to such position relative According .to .such application,v briefly .stated,'the' elements foraraisingand lowering as.

to the rest of the trackway that the cover can then be moved away from the furnace opening. Conversely, by lowering the said section out of the general plane of the trackway, the cover can be returned to its closing position. track section and therewith simultaneously the cover is advantageously positioned exteriorly-of the furnace beneath the trackway or the movable track section, where such apparatus is beyond any prejudicial effect ofheat coming-from the furnace. The apparatus for moving the cover, which is directly mounted for movement on the trackway and which does not have to bear the load of the raising and lowering means, is positioned beyond the cover and is separate from said last-named means.

Presently-preferred exemplary embodiments of the invention are hereinafter described in detail with reference to the accompanying sheets of drawing. On the said sheets of drawing,

Fig. 1 is a vertical section, somewhat diagrammatic, through the cover and its mounting on the trackway positioned alongside of the furnace opening;

Fig. 2 is a top plan View of the cover and its tracky;

Fig. 3 is a side elevation, showing the trackway section whichcan be raised and lowered; and

Figs. 4, 5 and 6 are views, somewhat diagrammatic, of various embodiments of apparatus for raising, and lowering the trackway section carrying the cover.

The pit or furnace chamber 1, only the top of which is shown on'the drawings, is tightly sealed at the top by the flat cover 3 which is provided on all four sides with a continuous depending flange 3 which extends into the sand pocket 2 which, correspondingly, extends continuously around the top of the pit or furnace chamber 1. The apparatus according to the present invention functions to remove the cover 3 from audio replace it J,

to its closing position.

According to the invention, the cover'3 is provided with a framework 4a which comprises journals for wheels 4 whereby the cover can be directly'mounted on the trackway 5 arranged alongside of the furnace opening on each side thereof. The trackway comprises a section 5a which supports the cover 3 when it is in position above the furnace opening, said section being arranged so that it can be raised and lowered relative to the rest of the trackway 5; The extent of such up and down movement may, for example, correspond to the amount necessary to lift the flange 3 from the sand pocket 2. The rest of the trackway 5 is of essentially, conventional structure comprising the usual track rails (a single track on each side of the furnace) and conventional supporting .beams.

The apparatus for lifting and lowering the sectionSawith the cover thereon, which apparatus is, as aforesaid, preferably located beneath the said section, may be of various constructions forms.

One embodiment of this apparatus is illustrated in Figs;

1 to 4 inclusive. This embodiment comprises lifting spindles 6one on each side of the furnace (see Figs. 3 and 4)for raising and lowering the trackway section 5a.

The source of motive power for actuating the spindles 6 is the motor M (Fig. 2) which is fixedly positioned .at a

point near the furnace which, however, is not exposed meshingconical gears provided on shafts 10 and -spin-- dles. 6, .as illustrated e. g. in Figs. 1, 3 and 4. This results in rotation of the lifting spindles 6 about the-longitudinal The apparatus for raising and lowering the said axes thereof. The upper flanged ends 8 of the spindles 6 being threadedly engaged with their respective lifting heads 7, rotation of spindles 6 causes upward or downward movement of the heads 7 and of the section a integrally secured thereto, in accordance with the direction of rotation of the spindles. The motor M may be bi-directional or the change in direction may be accomplished as desired through the medium of the gear boX G.

To facilitate rotation of the spindles 6, which carry the load of the section 5a and of the cover 3, the spindles are provided with fixed thrust ball bearings 11 (Fig. 4).

Shallow recesses 5b provided on the tracks of the movable section 5a to receive the wheels 4 of the cover 3 hold the cover in position on the said section during the upward and downward movement of the latter. These recesses also assure the correct positioning of the cover over the furnace chamber 1.

The supporting beam understructure of the trackway comprises beam 50 on the fixed portion and beams 5d on the movable portion 5a which are spaced apart by the distance x (see e. g. Fig. 4) which corresponds to the extent of the desired upward and downward movement of the movable trackway section.

Operation of the device will be clear from the foregoing. In the position shown in Fig. 4, corresponding to the raised position of the cover, the trackway section 5a i at the level of the remainder of the trackway, so that the wheels 4 may run on the tracks whereby the cover may be moved away from the furnace opening, e. g. to the left in Figs. 2 and 3, whereupon free access is had to the furnace for charging or discharging, etc. When it is desired to replace the cover 3 on the furnace chamber 1, the wheels are run back into the position shown on Fig. 4, i. e. so that the wheels are in their respective shallow recesses 5b on the trackway section 512. The cover 3 is then correctly positioned relatively to the furnace opening. To lower the cover into closing position, motor M is operated, power passes from the latter through the aforementioned shafts and gears to the spindles 6 which, rotating in the appropriate direction, cause downward movement of the spindle heads 7 and of the trackway section Sa. To open the furnace, the spindles 6 are rotated on the reverse direction whereupon heads 7 and section 5a are raised until the track portions on the latter are in alinement with the tracks on the remainder of the trackway whereby movement of the cover on the trackway may be effected, as aforedescribed. It goes without saying that movement of this character is impossible when the section 5a is depressed and the tracks thereof are out of line with the tracks of the remainder of the trackway.

An alternative embodiment is disclosed in Fig. 5, in which use is made of toggle levers or bent knee type levers. In this embodiment, the shafts 10 are not provided with cone gears as in the first-described embodiment. Instead, each of the two shafts 10 terminates in a threaded portion which cooperates with a correspondingly interiorly-threaded sleeve 13 which is provided at its outer end with a traveling nut 14 which is mounted for movement on slotted tube 12. Tube 12 is pivoted at one end to the supporting framework as shown and at the other end to the lower end of lever 15 of the toggle. The other end of lever 15 is hinged, as shown, to a lifting head 16 mounted in bushing 17, the upper end of the said head being integrated with the movable trackway section 5a. The toggle lever construction is essentially conventional and is per se no part of the present invention. It will be manifest that upon rotation of the shaft 10 in the appropriate direction (driven as in the previous embodiment from motor M), sleeve 13 will move to the left (as seen in Fig. 5) thereby bringing levers 12 and 15 into the vertically alined position (shown in broken lines in Fig. 5) and correspondingly raising the section 5a and the cover 3 whereupon the latter can be removed sure or water pressure, i. e. hydraulically.

from the furnace. In this embodiment, the shafts 10 do not, as in the previous embodiments extend to the far end of the section 511. Nor is it necessary to have more than one Working connection 12, 13, 14 on each side of the furnace. This connection is on each side connected by means of a rod 18 to a simple toggle lever connection 12, 15' (provided with conventional means for compensating for shortening when the lever assumes the vertical position shown in broken lines at the right of Fig. 5). The lever 12, 15 is connected at its lower end to the fixed framework and at its upper end to a lifting head 16. It will be clear that each set of parts 12', 15', 16 duplicates the movements of the corresponding previously described set of parts 12, 15, 16. It will also be clear that upon downward movement of the section 5a, the aforedescribed movements of the several parts of this embodiment will be in the reverse directions. Beams provided on section 5a and on trackway 5 are spaced apart by a distance x, as shown on the drawing.

In the embodiment according to Fig. 6, the raising and lowering of the trackway section 5a is effected by means of inclined planes 19 which are provided with rollers 19' which move in corresponding runways provided on the fixed framework of the trackway 5. In this embodiment, the trackway section 511 which as before is integrally associated with cover 3 rests on the four inclined planes 19 (the two shown in Fig. 6 being duplicated on the other side of the furnace), actual contact being made by rollers 20 journaled in the section 5a. When the rollers 20 are at the top of the respective inclined planes or wedges 19, i. e. in the full line position shown on the drawing, the rails on section 5a are alined with those of the remainder of trackway 5 and the raised cover 3 can be moved away from the furnace opening. As the inclined planes 19 move toward the central beam 5e of the supporting framework, the rollers roll downward along their respective planes and correspondingly lower the section 5a and the cover 3 which is in position thereon. As in the preceding embodiments, the source of power is motor M which power is transmitted to the two shafts 10 which in turn move the inclined planes 19. To this end each shaft 10 is provided adjacent to nearest inclined plane with a threaded portion which cooperates with a traveling nut 21 mounted on the said plane, and is provided adjacent the remote inclined plane with an oppositely threaded portion which cooperates with a traveling nut 21 mounted on the last-mentioned inclined plane. Beam 52 extends upwardly :to a distance x from the bottom of section 5a when the latter is in the position shown in Fig. 6. Rotation of shafts 10 will move the wedges 19 of each pair toward or away from each other, depending upon the direction of rotation of the said shafts, and will correspondingly raise or lower the section 5a and cover 3.

Any suitable and per se conventional means may be provided for effecting the travel of the cover 3 on the rails of the trackway. Fig. 3 diagrammatically shows such a means in the form of a motor 22 fixedly mounted at a point remote from the furnace and being connected to the cover 3 by means of a chain or belt 23 which runs over sprocket wheels or pulleys 24, the motor and the latter being capable of running in either direction.

Reverting to the first-described embodiment (Figs. 1 to 4), this can be modified so as to effect the raising and lowering of the trackway section 5a by means of oil pres- In such case, the lifting heads 7 with spindles 6 are replaced by lifting cylinders with correspondingly actuated lifting pistons.

Having thus disclosed the invention, what is claimed 1. Apparatus for raising and lowering and for transporting the cover of an upwardly open furnace or the like, the furnace opening of which is sealed by a vertical seal including a vertical flange depending from said cover into a sealing sand-containing pocket disposed continuously around said opening, said depending flange being correspondingly continuous so that in lowered position of said cover a gas-tight seal may be realized, comprising a trackway on each side of the furnace, means for directly supporting said cover at a plurality of horizontally spaced points on said trackways for movement thereon, each said trackway comprising a vertically movable horizontal trackway section, means for moving said cover in a horizontal direction onto said section and for entirely removing it in a horizontal direction therefrom, said cover being properly alined with the opening of said furnace when in position on said sections, the cover being in raised position when the trackway and trackway section on each side of the furnace are in alinement, means for vertically raising and lowering said trackway sections while maintaining said sections in constantly horizontal position and said sealing flange in constantly vertical position, said cover being in closed position on said furnace when said sections are in the lowered position thereof.

2. Apparatus according to claim 1, said means for raising and lowering said trackway sections being disposed exteriorly of said furnace and beneath said trackway sections.

3. Apparatus according to claim 2, wherein said raising and lowering means comprises lifting spindles.

4. Apparatus according to claim 3, wherein said lifting spindles are provided with ball thrust bearings.

5. Apparatus according to claim 1, said means for raising and lowering said trackway sections being disposed exteriorly of said furnace and beneath said trackway sections, said means being mechanically actuated.

6. Apparatus according to claim 1, said means for raising and lowering said trackway sections being disposed exteriorly of said furnace and comprising runways beneath said trackway sections, wedge blocks mounted on said runways, roller means mounted on said trackway sections for rolling contact with said wedges, and means for imparting horizontal sliding movement to said wedges whereby upon such movement relative vertical movement of said trackway sections is realized.

7. Apparatus for raising and lowering and for transporting the cover of an upwardly open furnace or the like, the furnace opening of which is sealed by a vertical seal including a vertical flange depending from said cover into a sealing sand-containing pocket disposed continuously around said opening, said depending flange being correspondingly continuous so that in lowered position of said cover a gas-tight seal may be realized, comprising a track way on each side of the furnace, means for directly supporting said cover at a plurality of horizontally spaced points on said trackways for movement thereon, each said trackway comprising a vertically movable horizontal "trackway section, means for moving said cover in a horizontal direction onto said section and for entirely removing it in a horizontal direction therefrom, said cover being properly alined with the opening of said furnace when in position on said sections, the cover being in raised position when the trackway and trackway section on each side of the furnace are in alinement, toggle lever means for vertically raising and lowering said trackway sections while maintaining said sections in constantly horizontal position and said sealing flange in constantly vertical position, said cover being in closed position on said furnace when said sections are in the lowered position thereof.

8. Apparatus for raising and lowering and for transporting the cover of an upwardly open furnace or the like, the furnace opening of which is sealed by a vertical seal including a vertical flange depending from said cover into a sealing sand-containing pocket disposed continuously around said opening, said depending flange being correspondingly continuous so that in lowered position of said cover a gas-tight seal may be realized, comprising a track way on which said cover is directly mounted for movement relative to said trackway, said trackway comprising a vertically movable horizontal sec-tion which is movable upwardly to a position wherein it is in alinement with the remainder of said trackway and downwardly to a position wherein it is out of such alinement, said section being arranged in alinement with the furnace opening whereby, when the cover is on said section, the cover is similarly in alinement with said opening, said cover being raised from said furnace when the said section is in raised position and being in closed position on the furnace opening when the said section is in lowered position, means to vertically raise and lower said section while maintaining the same in constantly horizontal position and said sealing flange in constantly vertical position, and means for moving said cover in a horizontal direction onto said section and for entirely removing it in a horizontal direction therefrom.

References Cited in the file of this patent UNITED STATES PATENTS 498,155 Commun May 23, 1893 1,655,478 Rockefeller Jan. 10, 1928 2,474,505 West June 28, 1949 

